I recently discovered rot in the main bulkhead where the upper shroud chainplate attaches. This is a fairly substantial bulkhead - about 1" thick. The roted area is roughly 2 inches wide by 12" high at the upper hull edge of the bulkhead.

Do anyone think that I can fill the area with thickened epoxy or should I be attemting to replace the area with a shaped piece of plywood? Replacing the total bulkhead would be a major piece of work as so much of the interior joinery is attached to this bulkhead.